When investigating the pH (acidic, neutral, alkaline) of a liquid, don't soak the litmus paper completely in the liquid but just put the end of the paper in it.
1. indicates direct object of action
2. indicates subject of causative expression
3. indicates an area traversed
4. indicates time (period) over which action takes place
5. indicates point of departure or separation of action
6. indicates object of d...
1. at (place, time), in, on, during
2. to (direction, state), toward, into
3. for (purpose)
4. because of (reason), for, with
5. by, from
6. as (i.e. in the role of)
7. per, in, for, a (e.g. "once a month")
8. and, in addition to
9. if, although
